Need pistons for my build, need some input

[WogsRus]

Hi guys

 

Well i am building my L26 and i want a set of pistons. I am going for flat tops with valve recesses and a N42 head shave 1mm for a 9.xx:1 compression ratio, more ore less still in design stage.

 

I am havign dificuulty finding pistons in Oz for a 240/260z flat tops with valve recesses.

 

I have found a set in the US from a L24E as per the atached pic

 

from what i gather it has a 2mm ring 2mm ring and a 4mm oil ring, i got the bore and so forth but in teh pic it looks like it has valve recesses and a bit of a dish.

 

Anyone got any ideas.

 

the seller states the following

 

hi

the piston sizes are

83.00 mm  diameter

78.00 mm  length

38.00 mm  compression distance (distance from top of the piston to the center of the pin)

0.80 mm  recessed  head

21.00 mm  pin size

 

 

what is the 0.8mm recessed head? also what is the L26 rods pin size?

 

anyone with help would be great.

 

PS. Where do i get a good set of pistons from?

 

 

 

[bluerat]

Howdy Cheif,

 

Merv Grey Automotive in Launceston just supplied flat tops for my L20, and they cut valve reccess into them, they are slow but very good, worth a try.

 

Hodgo.

[dat2kman]

JE or CP ( both in USA) will make you exactly what you want and need, you'd be looking at around $1500 AUD

There are piston manuf in Aus, try Ross Pistons.

Otherwise try Stewart Wilkins Automotive /Rallying he is in Penrith area NSW.

It would seem that you are not trying to "re -invent" the wheel, and by keeping it close to stock, will keep costs down.

 

FWIW I  have used in a L28 ( 79mm stroke)with L24 rods, Isuzu/Gemini G200 87mm slugs, with a bit shaved off the top ( flat - no dish) 22mm pins, much lower pin to top compression height. Improves my rod to stroke ratio for higher rpm power delivery.

Only issue I have had is that the bottom skirts on thes ( they are cast alloy, not forged) tend to break off and score the bores due to piston slap, mind you I rev it to over 7000.

I now use forged from CP with carefull attention to design/oiling/ring thickness etc.

[WogsRus]

yeah my whole engine build will cost $1500 or so so paying for custom pistons is a bit much.

 

Can you PM me details fo your engine build.

 

thanks

[aegean]

You can also try these guys. They only charge US$690 for a set of pistons.

 

http://www.paeco.com/Piston%20Ordering.htm

[260Coupe]

Go to Stewart Wilkins and get a set of standard flat tops and then have them fly cut to allow for the valve clearance. You will have to measure the lift and duration of the valves to calculate the depth.....My L26 with flatties had approz 2.3mm fly cuts from memory.

 

If you get really stuck then I have aset of Genuine Standard L24 pistons BNIB I may be willing to sell.....PM me if you want

[WogsRus]

well i will be shaving about 1mm of the head, depending what the CC of the head is after i have finished with it.

 

As for cam that is a little undecided as yet, but i will most likely only run a stage 2 cam as they call it, so 270 with 0.46 lift i think.

 

How do you calulate the fly cut depth? Sorry never had to customise stuff everytime previously i rebuilt engines it was stock for stock only.

 

 

 

[Scoota G]

Here was a set that i was looking at (maily because they were available in 40 thou oversize)

 

http://www.pistons-online.com/sport.asp?make=Nissan&st=33&end=33

 

But again pricey.

[WogsRus]

not to bad, but i want a budget build well a resonable budget build.

[aegean]

There is always these ones. I've had my eye on them for a while

 

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=190325209587&viewitem=&sspagename=STRK%3AMEWAX%3AIT